Devices for handling annular charges



April 22, 1969 M. LAPiERRx-z DEVICES FOR HANDLING ANNULAR CHARGES Sheetof 3 Filed June 15, 1966 iig* iiiiii April 22, 1969 M. LAPIERRE3,440,139

DEVICES FOR HANDLING ANNULAR CHARGES Filed June 1s, 1966 sheet of sApril 22, 1969 M. LAPIERR 3,440.139

DEVICES FOR HANDLING ANNULAR CHARGES med June 1s, 196e sheet 3 er sUnited States Patent O 3,440,139 DEVICES FOR HANDLING ANNULAR CHARGESMaurice Lapierre, Chelles, France, assignor to Societe dExploitation desMateriels Hispano-Suiza, Rue du Capitaine Guynemer, France Filed June13, 1966, Ser. No. 557,192 Claims priority, application France, June 21,1965,

Inf. ci. zlc 3/36 U.S. Cl. 176-30 9 Claims ABSTRACT F THE DISCLOSURE Aninstallation for handling a plurality of vertically stacked annular fuelelements including a support member for supporting the stack of fuele'lements and positioned between the lowest annular fuel element and thebottom of the channel in which the fuel elements are located. A tubularprobe having a catching device located at one end thereof, and movablebetween an expanded and a retracted position, is movable through thesaid annular passage with the catching device iu the retracted position;after which the catching device is expanded to engage the support memberfor removing the support member and the stack of annular fuel elementsupon upward movement of the tubular probe. The catching device mayinclude fingers pivotable about an axis from the retracted positionwithin the tubular probe to an expanded position whereat the lingersengage an internal bearing surface on the supporting member.

The invention relates to devices for handling annular charges having acentral passage open at both of its ends. The expression devicecomprises the handling apparatus and the annular charges to be handled-by said apparatus.

The invention is more especially but not exclusively concerned withdevices of this kind for handling annular fuel elements of nuclearreactors. The handling consists particularly in removing these fuelelements from reactor channels or in introd-ucing these elements intosaid channel.

The chief object of the present invention is to provide a device of theabove described kind which is better adapted to meet the requirements ofpractice than those used up to this time.

A device according to the present invention comprises a sounding rodhaving an operating end adapted to move from one end of the centralpassage to the other end, main catching means provided at this operatingend and adapted to have two different positions, to wit a retracted oneand an expanded one and control means adapted to place said maincatching means either in said retracted position or in said expandedposition.

A supporting part is connected with the annular charge to be handled, atthe end thereof opposed to that from which said rod is introduced intothe central passage, said supporting part being adapted to cooperatewith the main catching means in their expanded position for removing thecharges from the channel by retracting movement of the rod.

Preferred embodiments of the present invention will be hereinafterdescribed with reference to the appended drawings in which:

FIG. 1 is an axial section with parts in view of a device for handlingannular fuel elements of a nuclear reactor, according to the mainfeature of the invention.

FIGS. 2 and 3 are partial sections, on a larger scale, of parts of thedevice shown in FIG. l.

In a nuclear reactor, the annular fuel elements, which are generallycalled cartridges, are introduced in ver- ICC tical channels. Everyvertical channel 1 opens at its upper end, at the level of a plate 2shown in FIG. 1.

The fuel cartridges are piled up so as to form a column in every reactorchannel 1, each cartridge 3 comprises A casing 4, generally in graphite,the outer diameter of which is slightly lower than the inner diameter ofchannel 1, in such manner that casing 4 may slide in channel 1,

And a fuel element can, generally in magnesium, provided with outer fins5a ensuring the centering of said fuel element can 5 in casing 4, andinner fins 5b lhaving a central passage 6 coaxial with said casing 4,said fuel element can being 4maintained in said casing 4 -by wires 7generally in steel.

The charge of a channel of a nuclear reactor comprises generally a lowercartridge 3a having no fuel element and located at the lower part ofchannel 1, a given nurnber of fuel cartridges 3 piled lup on oneanother, the lower fuel cartridge thereof being carried by cartridge 3and an upper cartridge 3b approximately identical to fuel cartridges 3,but having no fuel, said cartridge 3b -being disposed at the upper partof channel 1 on the column of fuel cartridges 3.

It is reminded that up to this date the handling of fuel cartridges 3and cartridges 3a and 3b was eiectuated by a device carrying them attheir upper part. Such a device cooperates also with the upper part ofcasing 4 of the cartridge to -be handled.

Such handling has two inconveniences, to wit:

It is necessary to remove first the -upper cartridge 3b, then everycartridge 3 and finally the lower cartridge 3a,

The channel 1 may be closed when the upper part of casing 4 of saidcartridges 3 or cartridges 3a and 3b is destroyed accidentally.

In this last case, all the fuel cartridges and the lower cartridgeslocated under the cartridges 3a or 3b the casing of which is destroyed,are unaccessible to the removing device.

The main object of the present invention is to prevent the abovementioned inconveniences.

According to the invention, for handling fuel ca rtridges 3 andcartridges 3a and 3b of a nuclear reactor, a sounding rod 8 is used.Said sounding rod has an operating end adapted to move from one end ofthe central passage to the other end. Operating end 8 is provided withmain catching means 9 capable, under the action of control means, tohave either a retracted position or an expanded position.

A supporting part 10 is connected to the charge to be handled at the endthereof opposed to that from which said sounding rod is introduced intothe central passage. Supporting part 10 is adapted to cooperate withmain catching means 9 in their expanded position for removing thecharges fro-m the channel by retracting movement of said sounding rod 8.

According to a first embodiment of the invention, the charge to behandled is constituted by only a part of the column of cartridges piledup in the channel that is considered.

According to another feature of the invention, the charge to be handledconstitutes all the cartridges of the column and cartridges 3a and 3bpiled up in the channel that is considered.

This last solution is adopted for the following description. Thissolution is advantageous because it necessitates only one operation forcharging or removing every reactor channel.

FIG. 1 shows a sleeve 11 located between lower cartridge 3 and thebottom of channel 1. Sleeve 11 has an outer diameter approximately equalto the outer diameter of casing 4 of fuel cartridges 3 and cartridges 3aand 3b.

The inner walls of sleeve 11 are so arranged to constitute supportingpart 10.

Sleeve 11 supports lower cartridge 3a, the column of fuel cartridges 3and the upper cartridge 3b. It is constituted by a material having goodmechanical characteristics, such as steel. It is advantageous fornormalisation reasons, to give to the whole lower cartridge 3-sleeve 11,an axial length equal to the axial length of one of fuel cartridges 3 orof upper cartridge 3b. The depth of channel 1 is a multiple of saidcommon axial length. Main catching means 9 are constituted, as shown inFIGS. 1 and 2, by a device having three pivoting fingers 12. These threefingers are disposed at 120 at the lower part 8a of sounding rod 8. Theymay, under the action of an appropriate control means which will bedescribed hereinafter, have two positions:

A retracted position shown by one of said three fingers 12 in drill anddotted lines in FIG. 2,

An expanded position corresponding to FIGS. l and 2 in which said threefingers 12 cooperate with supporting part 10 arranged in sleeve 11.

Every linger 12 is adapted to pivot about an axis 13 disposed in suchmanner that, when the finger that is considered has its retractedposition, it is approximately parallel to the sounding rod 8 axis, andthat, when the finger that is considered has its expanded position, itmakes, with the sounding rod 8 axis, an acute angle open upward, thisangle being about 30.

The second catching means 9a are carried by sounding rod 8 and locatedabove main catching means 9. Second catching means 9,., are capable,under the action of appropriate control means which will be describedhereinafter, to have either a retracted position or an expandedposition.

The second catching means 9a are adapted to cooperate, when they are intheir expanded position, with a supporting part 10a provided in the fuelelement can 5 of lower cartridge 3a, said supporting part 10 beinglocated at the bottom of lower fins 5b of said can.

The second catching means 9EL are also adapted to be expandedsimultaneously with main catching means 9 and permit, when the whole offuel cartridges 3 and of lower and upper cartridges 3a, 3b is to beremoved from channel 1, to ease wires 7 which maintain can 5 in casing 4and to prevent, if wires 7 are broken, that the can 5 of lower cartridge3a sticks into lingers 12 of the main catching means 9.

FIGS. 1 and 2 show that second catching means 9 are constituted by asystem having three pivoting fingers 12a. These three pivoting fingersare disposed in staggered relation at 120 with respect to three fingers12 of the main catching means 9. They may have either a retractedposition, shown in FIG. 2 in drill and dotted lines, or an expandedposition, shown in FIGS. l and 2.

FIGS. l and 2 show fingers 12 in their expanded position, cooperatingwith a supporting part 10a constituted by a portion 10b located at thebottom of inner fins 5b of the can 5 of lower cartridge 3a.

Every one of lingers 12a is pivoted about an axis 13a disposed in suchmanner that:

When the finger that is considered has its retracted position, it isessentially parallel to the axis of rod 8,

And when the finger that is considered has its expanded position, itmakes, with the axis of said rod 8, an acute angle, open upward, thisangle being about 30.

Main catching means and second catching means are both controlled bycommon control means which comprise a sliding tube 14 constituting theouter wall of rod 8, said sliding tube 14 comprising,

On the one hand, three rectangular openings 15 located opposite threefingers 12 of the main catching means 9, every one of said threerectangular openings 15 having an axial length approximately equal tothat of fingers 12,

And, on the other hand, three rectangular openings 15a located oppositefingers 12 of second catching means 9a,

every one of said three rectangular openings 15 having an axial lengthapproximately equal to the length of fingers 12,.

Motor means are provided for acting on sliding tube 14 in such mannerthat tube 14 may have:

An upper position, in which openings 15 and openings 15 are respectivelyabove the fingers 12 of main catching means 9 and the fingers 12 ofsecond catching means 9a, ngers 12 and 12,L being located in saidsliding tube 14,

And a lower position, in which openings 15- and openings 15a are drawnrespectively to the level of the fingers 12 of main catching means 9 andthe fingers 12a of second catching means 9a,

Said above mentioned fingers then spreading about sliding tube 14, underthe action of resilient means.

Said resilient means are constituted by a spring 16 acting on a plate 17for the lingers 12 of main catching means 9 and by a spring 16 acting ona plate 17 for the fingers 12a of second catching means 9a.

When sliding tube 14 is in its low position, the fingers 12 of maincatching means 9 stay in their expanded position only under the effectof spring 16.

In order to prevent, during the handling, all risks of disconnection inthe column of cartridges, locking means are provided to preventaccidental retraction of the fingers 12 of main catching means 9.

Said locking means are constituted by three abutments 18 adapted to leanon the three fingers 12 of main catching means 9 when these ngers are inexpanded position, said abutments 18 above mentioned are supported by ahead 19 mounted on a second rod 20 axially movable and adapted to have:

An upper position in which said locking means are in their retractedposition shown in drill and dotted lines in FIG. 2,

And a lower position in which said locking means are in their expandedposition shown in FIG. 2 and in which the three locking abutments 18cooperate with the three fingers 12.

Sliding tube 20 is mounted on a sliding support 21 adapted to have,under the action of appropriate motor means, an upper position and alower position, resilient means, such as spring 22, tending to applythree abutments 18 on three fingers 12, whatever the position of fingers12 may be.

Motor means acting on sliding tube 14 to draw it from its upper position(main and second catching means being in retracted position) to itslower position (main and second catching means being in expandedposition) and motor means acting on sliding support 21 to draw it fromits upper position (locking abutments 18 being in retracted position) toits lower position (locking abutments 18 being in expanded position),comprise, on the one hand, control means 23 located at the top of rod 8and, on the other hand, means adapted to rotate said control means.

Control means 23 comprise, on the one hand, a driving shaft 24 forrotating a first threaded rod 25 cooperating with a nut 26 rigid withsliding tube 14, two contacts 27 and 28 permitting to control theposition of said sliding tube 14 and, on the other hand, a driving shaft29 rotating a second threaded rod 30 cooperating with a nut 31 rigidwith sliding support 21, two contacts 32 and 33 permitting to controlthe position of said sliding support 21.

In order to have a good positioning of said means for rotating and ofsaid control means, a supporting part 34 is provided at the upper partof said control means 23, said supporting part 34 is also provided witha centering inclined surface 35 adapted to cooperate with a centeringfinger carried by said means for rotating said control means 23.

Sliding tube 14 is provided with passage orifices 36 shown in FIG. l.This prevents perturbation in the circulation of carbonic gas in channel1, caused by rod 8 when it is in central passage 6 of fuel cartridges 3and cartridges 3a and 3b.

The discharging of the device is as follows:

Sounding rod 8 is introduced into central passage 6 of the cartridgespiled up on one another in channel 1;

Sliding tube 14 is drawn to its lower position, indicated throughcontact 28, main and second catching means 9 and 9a being expanded;

Sliding support 21 is drawn to its lower position indicated throughcontact 33, main catching means 9 being locked by abutments 18;

Rod 8 is removed from channel 1, the column of cartridges is alsoremoved through lingers 12 of main catching means 9 and lingers 12a ofsecond catching means 9a;

Cartridges are stocked in a stocking channel;

Sliding support 21 is drawn to its upper position indicated throughcontact 32, main catching means 9 being unlocked;

Sliding tube 14 is drawn to its upper position, indicated throughcontact 27, main and second catching means being retracted;

Sounding rod 8 is removed from the channel.

In a general manner, while the above description discloses what aredeemed to be practical embodiments of the invention, said invention isnot limited thereto as there might be changes made in the arrangement,disposition and form of the parts without departing from the principleof the invention as comprehended within the scope of the appendedclaims.

What I claim is:

1. An installation for handling a plurality of annular fuel elementshaving substantially the same outer diameter and piled coaxially,vertically one above the other in a channel of a nuclear reactorcomprising, in combination, a tubular probe designed to pass completelythrough the central passage delined by the pile of annular fuelelements, the lower end of said probe having a main catching deviceattached thereto and moveable between a retracted position and anoperative expanded position, control means for keeping the main catchingdevice retracted as the probe passes downwardly through the centralpassage as defined by the annular fuel elements and for expanding thecatching device to the said expanded operative position after thecatching device has passed through said central passage, an annularsleeve member positioned between the lowest annular fuel element and thebottom of the channel, the outer diameter of the sleeve beingapproximately equal to the outer diameter of said annular fuel elements,and the upper surface of the sleeve being engaged by the bottom of thelowest annular fuel element such that the sleeve supports the weight ofthe lowest annular fuel element as well as the weight of the remainingannular fuel elements of the pile, the said sleeve further including aninternal bearing surface arranged to be engaged by the main catchingdevice when said device is expanded to said operative position, and saidcatching device being operative, in the expanded position, in responseto upward pulling of the tubular probe, to cause upward movement of thesleeve with all of the annular fuel elements piled on the sleeve, oneabove the other.

2. An installation as claimed in claim 1 further comprising a secondcatching device located above the main catching device, second controlmeans for moving the second catching device to a retracted position andto an operative expanded position, an additional bearing surface locatedon the lowest annular fuel element, and said second catching deviceengaging the said additional bearing surface when the second catchingdevice is in the operative expanded position.

3. An installation according to claim 2 wherein said second catchingdevice comprises second pivoting lingers having both an expandedposition in which the lingers cooperate with said additional bearingsurface provided in said lower annular fuel element, and said fingersalso having a retracted position.

4. An installation according to claim 3 wherein said second pivotinglingers are disposed in staggered relation with respect to the lingersof the main catching device.

5. An installation according to claim 2 further comprising means foroperating main catching device and said second catching devicesimultaneously.

6. An installation according to claim 1 wherein said main catchingdevice includes pivoting lingers regularly disposed at the lower part ofsaid probe, said lingers being operated by said control means to occupyeither a retracted position or an expanded position in which saidlingers cooperate with said sleeve.

'7. An installation according to claim 6, including locking means forpreventing accidental retraction of the lingers of said main catchingdevice.

8. A device according to claim 3 wherein said first and said secondcontrol means are constituted by common control means comprising asliding tube constituting the outer wall of said probe, said slidingtube including lirst rectangular openings, every one of said lirstopenings being located opposite a linger of said main catching deviceand having an axial length approximately equal to that of said lastmentioned lingers and second rectangular openings, every one of saidsecond openings being located opposite a linger of said second catchingdevice and having an axial length approximately equal to that of saidlast mentioned lingers, and motor means acting on said tube in suchmanner that said tube Imay have an upper position in which the lingersof said two catching devices are located in said sliding tube and alower position in which said lingers are spread about said sliding tube.

9. A device according to claim 8 wherein said sliding tube is providedwith a plurality of orifices adapted to accelerate the circulation of acooling gas through Said channel.

References Cited UNITED STATES PATENTS 2,305,320 12/ 1942 Rea 294-972,701,736 2/ 1955 Heppenstall 294-94 2,634,156 4/ 1953 Crimmel 294-953,072,549 1/ 1963 Koutz et al 176-15 FOREIGN PATENTS 6,403,921 10/ 1964Netherlands.

967,203 8/ 1964 Great Britain.

BENJAMIN R. PADGETT, Primary Examiner.

H. E. BEHREND, Assistant Examiner.

U.S. Cl. X.R. 294-90, 86, 97

